1. Field of the Invention
The instant disclosure relates to a sensing network system; in particular, to a sensing network system without a central server, and nodes and data processing method thereof, wherein the sensed data is stored in more than one node.
2. Description of Related Art
Currently, the sensing network system has been widely used in our daily life. For example, the home nursing service system, the monitoring system and the Internet of things are all sensing network systems. In the sensing network system, there are plenty of nodes set within a certain region, and these nodes are connected to a central server via the Internet. These nodes are, for instance, the photographing apparatus, the temperature sensing device, the electronic device with a positioning means or the like. The central server is, for instance, a cloud server that has or is linked with multiple cloud hard-disks. The data sensed by these nodes would be transmitted to the central server via the Internet so as to store the sensed data in the cloud hard-disks described above.
Please refer to FIG. 1. FIG. 1 shows a schematic diagram of a traditional sensing network system. The traditional sensing network system 1 comprises a plurality of nodes 101˜105, the Internet 12 and a set of cloud servers and hard-disks 13. The plurality of nodes 101˜105 are linked to the set of cloud servers and hard-disks 13 via the Internet 12. The set of cloud servers and hard-disks 13 has a plurality of cloud servers and a plurality of hard-disks and thus is considered as a central server.
Generally, if any of the nodes 101˜105 fails or is stolen, the sensed data stored therein would also be lost. Thus, it is necessary to use the set of cloud servers and hard-disks 13 described above to store and back-up the data sensed by the nodes 101˜105, which means that the traditional sensing network system 1 needs a plurality of cloud servers and a plurality of cloud hard-disks. As a result, a great cost is required for establishing the traditional sensing network system 1.
On the other hand, in the traditional sensing network system 1, the nodes 101˜105 often need to upload the self-sensed data to the set of cloud servers and hard-disks 13, but seldom need to download data therefrom. Therefore, the amount of uploading data is much more than the amount of downloading data, which results in an asymmetrical transmission. This asymmetrical transmission would further make the download bandwidth usage rate of the traditional sensing network system 1 worse.